title: Effects of the comminution rate and microbial contamination of particles in the rumen on in situ estimates of protein and amino acid digestion of expeller palm kernel and rapeseed meal.
abstract: BACKGROUND
  Microbial corrected effective in situ estimates of ruminal undegraded fraction (RU) and intestinal effective digestibility (IED) of dry matter (DM), crude protein (CP) and amino acids (AA) of expeller palm kernel (EPK) and rapeseed meal (RSM) were measured on three rumen- and duodenum-cannulated wethers using ¹⁵N labelling techniques and considering ruminal rates of comminution (k(c)) and outflow (k(p)) of particles.
  
  
  RESULTS
  The lack of k(c) and microbial correction overestimated the RU of DM by 4.91% (EPK) and 9.88% (RSM). The lack of this correction also overestimated in both feeds the RU of CP, individual and total (TAA) AA as well as the IED of DM, CP, TAA and most AA. RU estimates were higher for CP than for TAA, but the opposite was observed for IED. The intestinal digested fraction was higher for CP than for TAA: 17.4% (EPK) and 13.8% (RSM). Digestion led to large changes in the essential AA profile in both feeds.
  
  
  CONCLUSIONS
  The lack of k(c) and microbial correction as well as CP-based results leads to considerable overestimations in the protein use of both feeds. Digestion aggravates the lysine deficiency of EPK but has global positive effects in the absorbed profile of RSM.
authors.affiliation: Departamento de Producción Animal, Escuela Técnica Superior de Ingenieros Agrónomos, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040, Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: González
authors.forename: José M
authors.initials: JM
authors.lastname: Arroyo
authors.forename: Rabiaa
authors.initials: R
authors.lastname: Mouhbi
authors.forename: Jesús A
authors.initials: JA
authors.lastname: Guevara-González
authors.forename: Vicente J
authors.initials: VJ
authors.lastname: Moya
authors.forename: Olga
authors.initials: O
authors.lastname: Piquer
mesh_terms: D000596:Amino Acids / Q000172:deficiency / Q000191:economics / Q000378:metabolism*; D000821:Animal Feed / Q000009:adverse effects / Q000032:analysis* / Q000191:economics; D000818:Animals; D028023:Arecaceae / Q000737:chemistry; D029741:Brassica rapa / Q000737:chemistry; D003677:Deficiency Diseases / Q000517:prevention & control / Q000662:veterinary; D004044:Dietary Proteins / Q000009:adverse effects / Q000191:economics / Q000378:metabolism*; D004063:Digestion; D005746:Gastric Emptying; D007220:Industrial Waste / Q000009:adverse effects / Q000032:analysis / Q000191:economics; D008239:Lysine / Q000172:deficiency / Q000191:economics / Q000378:metabolism; D008297:Male; D008954:Models, Biological; D009753:Nutritive Value; D010316:Particle Size; D010940:Plant Proteins / Q000009:adverse effects / Q000191:economics / Q000378:metabolism; D059748:Proteolysis; D012417:Rumen / Q000378:metabolism* / Q000382:microbiology; D012639:Seeds / Q000737:chemistry; D034561:Sheep, Domestic / Q000378:metabolism* / Q000382:microbiology
chemical_list: D000596:Amino Acids; D004044:Dietary Proteins; D007220:Industrial Waste; D010940:Plant Proteins; D008239:Lysine
keywords: amino acids; intestinal digestibility; protein; ruminal degradability; sheep